Does anyone Know how to remove the black trim plastic on the side of the s10 without harming the paint? It stretchs from the front quarter panel to beginning of my bed.  

Is it on a first gen S-10 ? Use a piece of heavy fishing line between it and the tape , working it back and forth . It should work pretty well , or use a piece of welding wire . Then use bug and tar remover or adhesive remover to get the rest of the tape off .  

Idk it is a 2003  

will doing what u said dent or pull out the body of the door and bed?  

it shouldn't , it is what most body guys do when they remove it to paint , well , the ones that do it right anyways . Some people out there just tape it off and paint around it . LOL .